SharePoint library Title field disconnect from Word default Title field

Hi Guy,

Recently, I am experiencing a tricky issue, hope I can get some help here. Here's the case:

I am using SharePoint 2019, there's a library has content type enabled. I have uploaded a custom word template for it.

The problem is that when I create a new document with the template(I cleared all of the document properties by: File->Info->Check for issues->Inspect Document->Inspect->Remove all Document properties and Personal Information), I filled in the Tile field by SharePoint Properties on the right-panel. (By the way, I am using Microsoft 365). But the value does not sync to the Document Properties. 

Any suggestions how to fix this issue?